Patients undergoing surgery of digestive organs are generally unable to orally receive nourishment and therefore usually subjected to intravenous hyperalimentation (IVH). For IVH, carbohydrates, amino acids and electrolytes serving as nutrients are usually given, whereas for example if glucose and amino acids are preserved as enclosed in a single container, the mixture becomes brown due to the so-called Maillard reaction. Accordingly, these different kinds of medicaments need to be contained separately. For this reason, medical containers having a plurality of chambers for enclosing such medicaments are introduced into wide use in recent years.
Such a medical container comprises two chambers, for example, for respectively enclosing a parenteral solution containing amino acids and a parenteral solution containing glucose, and a seal portion partitioning these chambers separately. The seal portion is so adapted as to usually close a space between the two chambers and to open the space for use. When one of the chambers is pressed for use, an increased internal pressure of the chamber opens the seal portion to mix the medicaments in the two chambers together. When a conduit is then connected to an outlet provided in the container, the medicinal mixture can be given to the patient.
When IVH is used over a long period of time, it has been pointed out that the patient suffers from deficiencies of trace elements or vitamins which are not contained in the parenteral composition. However, since vitamin preparations are low in stability, it has been difficult to incorporate the vitamin preparation into the parenteral composition for IVH. To resolve this problem, the present applicant has proposed a multiple-chamber container as disclosed in WO, A1 No. 99/39679. The proposed container has, in addition to the conventional structure described, a small container enclosing a vitamin preparation therein and provided inside one of the chambers. The small container can be opened by being pressed from outside. When the medical container is to be used, the seal portion is opened to mix together the medicaments in the two chambers, and the small container in the chamber is opened by being pressed from outside to mix the vitamin preparation with the mixture.
The construction described above nevertheless involves the necessity of opening the small container in addition to the opening of the seal portion, hence the problem of a cumbersome procedure. Especially busy places of medical services, such a cumbersome procedure often burdens the worker heavily.
An object of the present invention, which has been accomplished to overcome this problem, is to provide a medical container comprising a plurality of chambers and adapted to readily and reliably open a small container therein.